I know that we're not answering your question, but with good reason.

• Folders are thief magnets, particularly the nicer ones. I would never lock my tikit up outside.
• Most locks are fairly straightforwardly defeated and people just don't care. A standard U-lock is breakable using just a 2x4 hunk of wood.
• Campuses are high-value targets for bike thieves.
• One of the advantages of a folder is that you can take it inside.

I'm a professor so I have somewhere inside to stash my bike of course. But trust me, you can bring a bike in a class if it's covered. Even if it's not covered, if it's folded the amazement factor sets in: people are so wowed by the folded form that they forget you just brought a bike into class. I've brought the tikit into an NSF grant panel. We have lots of students who bring their longboard skateboard into class. Be brave.

That being said, if you're planning on touring longer distances on it in Japan, you may wish to consider a folder other than a Brompton. Look into a tikit too.